Chloroplasts are found in the cells of plants that conduct photosynthesis. They absorb sunlight and use it along with water and carbon dioxide gas (CO2) to produce food for the plant.

Chloroplasts are the magic making masters. Inside the chloroplast, the pigment chlorophyll seems to turn light into matter, in fact using the energy of sunlight to make organic molecules. Chloroplasts were free-living cyanobacteria once.

Mitochondria generate the energy that cells need to function. The energy made by the mitochondria is in the form of a chemical called adenosine triphosphate or ATP.

Chloroplasts in a plant cell, in this case a spinach leaf. Inside the chloroplasts, the stacks of thylakoid membranes are where the action takes place. The dark spots are starch granules. In close proximity are the mitochondria, with curved membranes, and the endothelial reticulum. This system of membranes navigates between the energy producing organelles until it reaches the nucleus, where it also forms the nuclear membrane.